Sotalol hydrochloride (“sotalol”) is Vaughan Williams Class III anti-arrhythmic drug that prolongs cardiac action potential duration by blocking the outward potassium channel IKr (rapid potassium rectifier current), thereby prolonging repolarization time.
Although sotalol is effective at treating or preventing atrial fibrillation, atrial flutter, and combinations thereof, sotalol's mechanism of action is both anti-arrhythmic and pro-arrhythmic. Too much sotalol too fast can lead to excessive prolongation of repolarization time giving rise to life threatening arrhythmias, especially Torsade de Pointes ventricular tachycardia (Tdp). Thus, it is well understood in the art, that during sotalol's initial loading, or in a dose escalation intervention, it is critical to monitor a subject's QTc interval to avoid excessive QTc prolongation.
Due to sotalol's potential to induce arrhythmia, the FDA has mandated in-hospital QTc monitoring for at least three days upon initial sotalol hydrochloride loading and for dose escalation. Although this extended hospital stay is effective at reducing subject risk, maintaining the subject in a telemetry unit for three days is extremely expensive, making sotalol a less desirable treatment choice in a managed care environment. A need therefore exists to develop methods of reducing the length of hospital stay required to safely and efficaciously administer sotalol to subjects in need thereof.